Maybe we're all just overthinking it when it comes to figuring out where interest rates are headed over the long term.

Instead of parsing through data on unemployment, inflation and productivity, rather than scouring for the hidden meaning behind every little turn of a phrase in the post-Fed meeting statements, and in lieu of the debate between rules-based and data-driven policy, we could just look at one thing: a height chart.

fed chair height and interest rates comparison

After all, there's pretty clear evidence to suggest that over the past almost 40 years of monetary policy, the path of rates has had a near-perfect correlation with the physical stature of the Federal Reserve chair.

Take "Tall Paul" Volcker for instance. The 6-foot 7-inch former central banker and inflation slayer oversaw the surge of the Fed's benchmark funds rate from an average 11.2 percent in 1979 all the way to 20 percent by mid-1981.

Conversely, the more average-sized 5-foot 8-inch Ben Bernanke yanked the funds rate from 5.25 percent in June 2006 down to near zero by the end of 2008, a level where it stayed until December 2015.